And I'm Linda Wertheimer. In Syria, this week has been one of the bloodiest reported in months. Activists and groups monitoring Syria say hundreds have been killed as the government moves against villages and towns near the Turkish border. The Syrian government acknowledges the campaign but calls it a fight against terrorists.

In Washington, the White House condemned the rising death toll. The French government called it a massacre. And the head of the Arab League appealed to Syria to protect civilians. NPR's Deborah Amos is in Beirut monitoring the situation in Syria. Good morning, Deb.

DEBORAH AMOS, BYLINE: Good morning, Linda.

WERTHEIMER: First of all, what can you tell us about these clashes in northern Syria?

AMOS: Well, it appears that this latest offensive begins on Monday in northern Syria near the town of Idlib. There was a large number of soldiers, around 100, who had planned to defect, to make a run to the Turkish border. But they never made it. Those defectors were surrounded and most of them were shot. Now, these details have been pieced together over the past few days by activists who were in touch with people there by satellite phones.

Cell phone communication has been cut. It appears that after that event, the army started hunting down defectors, any of those wounded, and any civilians who'd given shelter to those defectors. So residents reported that the army surrounded some villages and started shelling, and that's when you have large numbers of civilian deaths. Somewhere around 100 people died in this campaign.

WERTHEIMER: Is it because they are so close to Turkey that this party of Syria is a flashpoint?

AMOS: That's part of it. It's also a mountainous area and that poses some problems for the regular army. This area has also been a hotbed of peaceful protest, where some of these small villages have, quote, "liberated themselves" over the past couple of months. So it's become a haven for army defectors. There's a growing supply line that's coming in from Turkey and the terrain makes it difficult for the army to operate against them.

It's often said that Syria's defectors hold no territory. There's no Benghazi. That's the place that Libyan rebels launched their offensive. But Idlib was kind of becoming Syria's Benghazi.

WERTHEIMER: Syria has agreed to an Arab League peace plan. An advance team is arriving in Syria today to implement that plan. Are these events connected?

AMOS: Some analysts say yes, that the Syrian regime wanted to clean out this nest of defectors before the Arab League monitors arrived. But there's a counter argument that this is the last thing the Syrian government wanted. It's the commanders on the ground who went too far up in the north. Washington has escalated the rhetoric. The French government called it an unprecedented massacre. And all this means is more pressure on the Syrian government, more pressure on its ally, Russia, to take some action.

WERTHEIMER: Deb, Syria accepted the Arab League peace plan under pressure. How are they going to implement it? Can these monitors go wherever they want? Can they see that the plan is actually carried out?

AMOS: Well, that remains to be seen. Today the advance team arrives to set up all this in Damascus. You know, this is unprecedented, Linda, in the Arab world. And so everybody has to figure out how to do it. There's 150 monitors. Their job is to see that Syria is abiding by the peace plan, and that includes withdrawing Syrian troops from the cities.

But if that happens, there's likely to be mass demonstrations. Syria has more to hide than it has to show, and that's what analysts out here say. So the idea is for the Arab League to stop the killing, but Syria wants them to prove that this is an attack by armed terrorists. There's already problems with this mission.

For example, today the Syrian opposition group, the SNC, charges that the head of the military mission is a Sudanese who is wanted at the International Criminal Court for acts against activists in Sudan. So you can see that there is going to be a lot of problems coming with this mission.

Do they get to go where they want to go? Will Syria hold them back in the capital? Can they see what's happening in the country? And the next steps in this crisis depend on the success or the failure of this Arab League mission.

WERTHEIMER: NPR's Deborah Amos is in Beirut. Deb, thank you very much.